The Global Partnership for Education's (GPE) interest in broader education workforce issues is situated within the context of the partnership's current strategic plan (GPE 2025), which recognizes "quality teaching" as a priority area within a wider system transformation agenda. GPE's work includes providing technical support in this area for the benefit of country operations, including the development and/or dissemination of tools and guidelines. Some GPE partner countries have shown particular interest in diagnostic or analytical tools to better understand the scope of their challenges related to quality teaching and the broader education workforce. Guidance in diagnosing the challenges of the education workforce and leveraging its potential for strengthened teaching and learning would be useful especially for those involved in preparing education sector plans or strategies, or specific programs aimed at improving teaching and learning. This paper: (1) Analyzes the guidance that prominent existing international frameworks and tools can provide for diagnosing challenges and strengths related to teachers and the broader education workforce. Special attention is given to tools dealing with teachers, teaching and learning and/or related policies and management, and for which several country applications have been reported. Challenges concerning the implementation and use of these tools are also explored tentatively through a set of interviews with professionals involved in their application and/or monitoring; (2) Attempts to identify the main gaps and challenges that remain to be addressed as regards the contents, methodology and implementation of future education workforce diagnostics; and (3) Suggests possible directions and considerations for the development of future education workforce diagnostic tools.